This section describes fine-grained permissions management for your OBS. If your account does not require individual IAM users, skip this section.
By default, new IAM users do not have any permissions assigned. You need to add a user to one or more groups, and attach IAM policies to these groups. The user then inherits permissions from the groups it is a member of. This process is called authorization. After authorization, the user can perform specified operations on OBS based on the IAM policies.
For details about user policies related to OBS, see Permissions Management in the "Service Overview" section of Object Storage Service User Guide. For details about the syntax and examples of IAM policies, see Console Operation Guide > Permissions Control > Permission Control Mechanisms > IAM Policies in the Object Storage Service User Guide. x.x.x indicates the version number.
There are fine-grained policies and role-based access control (RBAC) policies. An RBAC policy consists of permissions for an entire service. Users in a group with such a policy assigned are granted all of the permissions required for that service. A fine-grained policy consists of API-based permissions for operations on specific resource types. Fine-grained policies, as the name suggests, allow for more fine-grained control than RBAC policies.
- If you want to allow or deny the access to an API, fine-grained authorization is a good choice.
- Because of the cache, it takes about 10 to 15 minutes for the RBAC policy to take effect after being granted to users and user groups. After a fine-grained OBS policy is granted, it takes about 5 minutes for the policy to take effect.
An account has all of the permissions required to call all APIs, but IAM users must have the required permissions specifically assigned. The required permissions are determined by the actions supported by the API. Only users with the policies allowing for those actions can call the API successfully. For example, if an IAM user needs to create buckets using an API, the user must have been granted permissions that allow the obs:bucket:CreateBucket action.
Supported Actions
Operations supported by a fine-grained policy are specific to APIs. The following describes the headers of the actions provided in this section:
- Permissions: defined by actions in a custom policy
- APIs: REST APIs that can be called by a user who has been granted specific permissions
- Actions: specific operations that are allowed or denied in a custom policy
OBS supports the following actions in custom policies:
- Bucket-related actions include actions supported by all OBS bucket-related APIs, such as the APIs for listing all buckets, creating and deleting buckets, configuring bucket policies, configuring bucket event notification, configuring cross-region replication, and configuring bucket logging.
- Object-related actions include APIs for uploading, downloading, and deleting objects.